TMP had the best story in terms of staying true to TOS, but slow as hell. Khan was not a great villain. He spouted off cliched evil lines, and spouted off Shakespeare. I thought Nero was a better villain. In terms of characterization, Only Kirk, Spock, and Saavik gained the most. McCoy was redeemable in the last few minutes of the film, but Sulu did nothing. Uhura did nothing. Chekov went from a first officer to his same post. Scotty lost his nephew in accordance to what version you are watching, but he, also, did nothing. When I mean nothing, I mean something that they did to make themselves grow as a character. They did the exact same things from TMP and TOS. In TSFS, all the characters shined. Same with the TVH. In TFF, they were back to the norms again, like the last couple of movies didn't happen. In TUC, which I loved, only Sulu really went out of his established role, eveyone else stayed the same. Granted the actors got older, but they characters did not.
GEN was good, but we needed a better end for the Enterprise-D, and throw out the Duras Sisters. FC was excellent. INS was alright, lame villain. I was hoping for a semi-civil war as was seen from the first INS trailer, but oh well. NEM had the most potential, but failed miserabley in terms of villains and story. Only Dr Crusher stayed in the same mold from TNG,